Penn, Boone, and Sashi are zapped into an underwater world to save a society of fish people, but their mission gets complicated when Penn finds out that Boone is afraid of water.

Exhausted from recent missions, Penn is relieved when he is zapped into a seemingly ordinary job as a food court employee in a mall, but it turns out that Penn and his team are in an alternate world where a zombie apocalypse is taking place.

Penn and his team are zapped into a world where they are enormous yet misunderstood monsters. They must convince the human President of a nearby island city that the monsters mean them no harm.

When Penn and his team are zapped into a world where the colorful Hues and the gray Drabs are in a feud, they must stop Rippen from destroying the rainbow rocks, which provide the world's colors.

When Penn discovers that Phyllis is trying to locate the Most Dangerous World Imaginable to bring his parents back to Middleburg, he takes matters into his own hands leading to catastrophic results.

Penn tries to solve a twisted mystery in a world where everyone is a plant.

Penn and his friends merge as giant metamorphosing robots to fight for control of an alien planet.

Phil and Rippen tunnel into The Odyssey and damage the Multi Universe Transprojector, causing unbalance in the multiverse. Vortexes form in every world that Penn and his team have visited. Penn, Boone, and Sashi must travel to each world and close all of the vortexes before everything and everyone from all the worlds get sucked into nothingness. During their mission, Penn finds a crystal shard in the nothingness, which, according to Phyllis, is the key to finding his parents.

Penn has to stop Rippen from ruining a dinner in a sitcom dimension.